The invention relates to a mounting for an electric motor, particularly for an electric motor for a fan wheel of a heating or air-conditioning system of a motor vehicle, having a plurality of support elements made of a rubber-elastic material which are disposed distributed along the circumference of a pole ring of the electric motor.
In order to achieve the decoupling of oscillations and in this way to prevent the creation of noise on a housing or a vehicle, it is known (European Patent Publication EP 0 545 003 A2) to dispose strip-shaped rubber-elastic materials between the pole ring of an electric motor and a motor mount. In an exemplary embodiment, these rubber-elastic elements are positively connected with the motor mount. To secure the electric motor in the axial direction, this embodiment provides that the pole ring is equipped with one or a plurality of recesses which are engaged by button-shaped projections of the strip-shaped support means. In another exemplary embodiment it is provided that the motor mount is connected with the support bracket of the electric motor and that rubber-elastic materials are placed between them.
It is an object of the invention to provide a mount of the type mentioned at the outset which will result in an improved decoupling of oscillations.
This object is attained according to preferred embodiments of the invention in that the support elements are disposed between an adapter, which can be attached to the electric motor so that it is fixed in place at least in the axial direction, and a motor mount, and in that the support elements are positively connected with the motor mount at least in the axial direction.
A multi-piece mount into which the rubber-elastic support elements are integrated is created by means of an embodiment of the invention. The rubber-elastic elements do not directly act on the electric motor. Instead, the latter is received in the adapter of the mount, which can maintain the electric motor securely in the axial direction without it being necessary to make any changes, in particular to the pole ring.
In further embodiments of the invention it is provided that the support elements have an axial length approximately corresponding to between a third to a fourth of the axial length of the pole ring. In a practical manner it is further provided that the support elements are disposed in a common radial plane. In a preferred attainment of the object it is provided that the radial plane extends at least approximately through the axial. center of the unit comprised of the electric motor and the element driven by it, in particular a fan wheel. Because of this arrangement, the components comprising the electric motor and the driven element (fan wheel) can oscillate freely around their center, since the support elements allow these movements, without the oscillations being transmitted via the motor mount to a housing or the vehicle.
In connection with a structurally advantageous embodiment it is provided that the adapter and the motor mount can be inserted into each other in the axial direction, wherein the support elements disposed on the adapter enter receivers of the motor mount and are locked therein. A very simple assembly of the mounting results from this embodiment.
It is provided in an advantageous further embodiment that the fingers are provided on their exterior with respective projections which engage recesses of a support element. A positive connection between the adapter and the support elements is realized by means of this arrangement.
In a further embodiment of the invention it is provided that the motor is equipped with axially limited receivers which enclose a support element in a shell-shaped manner. These receivers, together with recesses for the locking projections of the support elements, result in a positive connection between the motor mount and the support elements.
In connection with a first embodiment of the invention it is provided that the adapter has a ring which encloses a front end of the pole ring and is provided with a plurality of fingers extending along generating lines of the pole ring and enclosing the other front end of the pole ring by means of locking projections, with support elements disposed on the fingers. The elastic fingers of this adapter make it possible to compensate for diameter tolerances of the pole rings of the electric motor.
In a further embodiment of the invention it is provided that the adapter essentially consists of a plurality of fingers extending along the generating lines of the pole ring of the electric motor, which are connected with each other by means of a strut extending transversely in respect to the motor shaft. This adapter can be applied to the electric motor without having to remove the fan wheel from the electric motor. Because of this, it is possible to balance the electric motor together with the fan wheel and to apply the adapter only later. With this embodiment no closed ring is pushed over the pole ring, so that this adapter is also suitable for electric motors with connecting elements or circuit elements projecting beyond the circumference of the pole ring. In an advantageous further embodiment it is provided that the adapter is a stamped and bent preformed sheet metal part. This preformed sheet metal part which can be manufactured in particular from aluminum also results in the advantage that heat removal from the pole ring of the electric motor is improved.
It is provided in a further embodiment that at their ends facing away from the strut the fingers of the adapter make a transition into a ring surrounding the pole ring of the electric motor. This adapter can be advantageously manufactured as a preformed plastic part. In this case the additional ring acts as a spring element keeping the fingers apart, so that the adapter can be easily pushed on the pole ring.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.